Development of high‑resolution melting analysis for ABCB1 promoter methylation: Clinical consequences in breast and ovarian carcinoma

Oncol Rep. 2019 Aug;42(2):763-774. doi: 10.3892/or.2019.7186. Epub 2019 Jun 5.


Multidrug resistance to anticancer drugs, which is often associated with enhanced expression of the ATP‑binding cassette (ABC) transporter P‑glycoprotein (encoded by the ABCB1 gene) may limit the effects of cancer therapy. Epigenetic regulation of ABCB1 expression may thus have a clinical impact. A detailed assessment of ABCB1 promoter methylation is of importance for predicting therapy outcome and prognosis. Thus, validated methods for the analysis of ABCB1 promoter methylation are urgently required. In the present study, high‑resolution melting (HRM) analysis of the CpG island regions covering the distal promoter of the ABCB1 gene was developed and compared with pyrosequencing. In addition, the clinical effects of the methylation status of the ABCB1 promoter were analyzed in patients with breast and ovarian carcinoma prior and subsequent to chemotherapy treatment. HRM analysis of ABCB1 methylation correlated with the results of pyrosequencing (P=0.001) demonstrating its analytical validity and utility. Hypermethylation of the analyzed ABCB1 promoter region was significantly correlated with low levels of the ABCB1 transcript in tumors from a subset of patients with breast and ovarian carcinoma prior to chemotherapy but not following treatment. Finally, high ABCB1 transcript levels were observed in tumors of patients with short progression‑free survival prior to chemotherapy. Our data suggest the existence of functional epigenetic changes in the ABCB1 gene with prognostic value in tumor tissues of patients with breast and ovarian carcinoma. The clinical importance of such changes should be further evaluated.

MeSH terms

  • ATP Binding Cassette Transporter, Subfamily B / genetics
  • Biomarkers, Tumor / genetics*
  • Breast Neoplasms / drug therapy
  • Breast Neoplasms / genetics
  • Breast Neoplasms / pathology*
  • Carcinoma, Ductal, Breast / drug therapy
  • Carcinoma, Ductal, Breast / genetics
  • Carcinoma, Ductal, Breast / pathology
  • Cystadenocarcinoma, Serous / drug therapy
  • Cystadenocarcinoma, Serous / genetics
  • Cystadenocarcinoma, Serous / pathology
  • DNA Methylation*
  • Epigenesis, Genetic
  • Female
  • Follow-Up Studies
  • Gene Expression Regulation, Neoplastic
  • Humans
  • Neoplasm Invasiveness
  • Nucleic Acid Denaturation
  • Ovarian Neoplasms / drug therapy
  • Ovarian Neoplasms / genetics
  • Ovarian Neoplasms / pathology*
  • Polymerase Chain Reaction / methods*
  • Prognosis
  • Promoter Regions, Genetic*
  • Retrospective Studies
  • Survival Rate


  • ABCB1 protein, human
  • ATP Binding Cassette Transporter, Subfamily B
  • Biomarkers, Tumor